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Submitted by arlindo kohlrausch (ajfk@uepg.br) on 2022-09-30T23:34:29Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Fernanda Antunes Martins.pdf: 699626 bytes, checksum: 5a15c7dc31863ff363bef3398c718e2a (MD5) Made available in DSpace on 2022-09-30T23:34:29Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Fernanda Antunes Martins.pdf: 699626 bytes, checksum: 5a15c7dc31863ff363bef3398c718e2a (MD5) Previous issue date: 2022-08-01 Um dos fatores que comprometem a qualidade do leite é a falta da estabilidade frente ao álcool. A instabilidade do leite causa prejuízos à indústria na produção de derivados lácteos, uma vez que o leite precipita quando submetido ao tratamento térmico. O objetivo da pesquisa foi analisar a estabilidade do leite de produtores do Estado do Paraná, por meio da prova do álcool sob seis concentrações e relacionar com os fatores que possam interferir sobre a estabilidade. Foram coletadas amostras de leite dos tanques de resfriamento dos produtores, sendo as coletas realizadas duas vezes no verão e duas vezes no inverno, gerando 425 e 389 amostras, respectivamente, totalizando 814 amostras. As propriedades foram classificadas de acordo com o nível de intensificação dos sistemas de produção: a pasto com suplementação (PS) e confinamento (CO). No laboratório, às amostras foram submetidas as análises de teste do álcool, acidez titulável e concentração de cálcio iônico (Cai), além da composição química do leite, contagem de células somáticas (CCS) e contagem padrão em placas (CPP). Foram realizadas análises descritivas e de correlação entre as variáveis. Na análise de variância foram avaliados a estação do ano (inverno ou verão) e o sistema de produção (PS ou CO). As análises de regressão logística foram calculadas para determinar a probabilidade de ocorrência de leite instável não ácido (LINA) nas concentrações alcoólicas de 72 e 78 °GL. Na análise de regressão linear múltipla, a estabilidade do leite foi considerada como a variável dependente. A estabilidade do leite foi maior no inverno e apresentou menores teores de Cai em relação ao verão. Quanto ao sistema de produção, verificou-se que as vacas mantidas em confinamento produziram leite com maior estabilidade e teor de lactose em comparação com as vacas criadas sob pastejo. A estabilidade teve correlação negativa com o Cai e positiva com o teor de lactose. A acidez titulável apresentou correlação positiva com a estabilidade, possivelmente devido à elevada acidez natural observada. A incidência de LINA considerando o álcool a 72 °GL foi de 12,16% e no álcool a 78°GL foi de 34,64%. Na regressão logística de risco de LINA72 apenas as variáveis Cai e lactose foram determinantes, enquanto no risco de LINA78 as variáveis determinantes foram o Cai, a acidez titulável, a lactose e o nitrogênio uréico no leite. Na regressão linear múltipla, a lactose (r2 parcial = 0,13) e o Cai (r 2 parcial = 0,06) foram as variáveis que apresentaram incremento linear significativo para a estabilidade do leite, no entanto, o modelo explica apenas 26,6% (r2 total = 0,266) da variação total. Nas condições de produção da pecuária leiteira do Paraná, a ocorrência de LINA72 foi baixa, sendo mais frequente no verão e no sistema de produção a pasto com suplementação. As variáveis determinantes e comuns ao LINA72 e LINA78 foram as concentrações de Cai e lactose. Portanto, comprova-se que a ocorrência do LINA no Estado do Paraná foi baixa e as causas foram multifatoriais. One of the factors that compromises the milk quality is the loss of stability in the face of alcohol. The milk instability impair the industry, in the production of dairy derivatives, since milk precipitates when subjected to high temperatures during thermal processing. The objective of the research was to analyze the milk stability from producers in the State of Paraná, through the alcohol test under six concentrations and to relate it to the factors that may interfere with the stability. Milk samples were collected from the producers' cooling tanks, being collected twice in the summer and twice in the winter, generating 425 and 389 samples, respectively, totaling 814 samples. The properties were classified according to the level of intensification of the production systems: pasture with supplementation (PS) and confinement (CO). In the laboratory, the samples were submitted to alcohol test, titratable acidity and ionic calcium concentration (Cai), chemical composition, somatic cell count (SCC) and standard plate count (SPC). Descriptive and correlation analyzes were performed. In the analysis of variance the season of the year (winter or summer) and the production system (PS or CO) were evaluated. Logistic regression analyzes were calculated to determine the probability of occurrence of unstable non-acid milk (UNAM) at alcohol concentrations of 72 and 78 °GL. In the multiple linear regression analysis, milk stability was considered as the dependent variable. Milk stability was higher in winter and presented lower levels of Cai compared to summer. Regarding the production system, it was found that cows kept in confinement produced milk with greater stability and lactose content compared to cows raised under grazing. Stability was negatively correlated with Cai and positively correlated with lactose content. The titratable acidity showed a positive correlation with stability, possibly due to the high natural acidity observed. The incidence of UNAM considering alcohol at 72°GL was 12.16% and in alcohol at 78°GL it was 34.64%. In the logistic regression of risk for UNAM72, only the variables Cai and lactose were determinants, while in Unam78 the determinant variables were Cai, titratable acidity, lactose and milk urea nitrogen. In the multiple linear regression, lactose (partial r2 = 0.13) and Cai (partial r2 = 0.06) were the variables that showed a significant linear increase for milk stability, however, the model explains only 26.6 % (total r2 = 0.266) of the total variation. Under the production conditions of dairy cattle in Paraná, the occurrence of UNAM72 was low, more frequently in the summer and in the pasture production system with supplementation. The determining and common variables for UNAM72 and UNAM78 were Cai and lactose concentrations. Therefore, it is proven that the occurrence of UNAM in the State of Paraná was low and the causes were multifactorial.

Few environmental issues have resulted in such a heated policy-science controversy in Sweden as the 1990s acidification debate in the north of the country. The belief that exceptionally high stream acidity levels during hydrological events was caused by anthropogenic deposition resulted in a governmentally funded, multi-million dollar surface-water liming program. This program was heavily criticized by a large part of the scientific community arguing that the acidity of northern streams was primarily caused by naturally occurring organic acids. Here, we revisit the acid deposition legacy in northern Sweden two decades after the culmination of the controversy by examining the long-term water chemistry trends in the Svartberget/Krycklan research catchment that became a nexus for the Swedish debate. In this reference stream, trends in acidic episodes do show a modest recovery that matches declines in acid deposition to pre-industrial levels, although stream acidity continues to be overwhelmingly driven by organic acidity. Yet there are legacies of acid deposition related to calcium losses from soils, which are more pronounced than anticipated. Finally, assessment of these trends are becoming increasingly complicated by new changes and threats to water resources that must be recognized to avoid unnecessary, expensive, and potentially counterproductive measures to adapt and mitigate human influences. Here we make the argument that while the acidification era is ending, climate change, land-use transitions, and long-range transport of other contaminants warrant close monitoring in the decades to come.

Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq The main interest of the soils acidity correction is to neutralize the exchangeable Al3+, since the presence of this form of Al in the soil causes restriction of root growth and consequently the decrease of the productivity of sensitive crops. Thus, monitoring the advance of attributes related to soil acidity in depth in cultivated areas is fundamental to assist in the decision of reapplication of acidity corrective forms. The aim of this study was to quantify the chemical changes in the soil caused by lime application with different Ca:Mg ratios, in a superficial and incorporated form after 141 months of its application. The experiment was installed in 2004 under native field in an Ultisol. The statistical design was a two-factor type with two types of application forms (incorporated and superficial) and five types of correctives (control, and calcareous with Ca:Mg molar ratio of 30.0 (calcitic); 9.0; 5.0 and 3.2 (dolomitic). In July 2016, 36 trenches were opened in each plot and soil samples were collected at depths of 0 to 60 cm. In the soil layer of 0 to 10 cm the soil samples were collected every 1 cm, in the layer of 10 to 25 cm the soil samples were collected every 2.5 cm and in the layer of 25 to 60 cm the samples of were collected every 5 cm. In total, 25 depths per trench were sampled, totaling 828 soil samples used for the chemical analyzes. The analysis performed were: values of pH in water in the ratio 1:1, TSM index (Santa Maria Buffer) and Ca, Mg and Al exchangeable. From these results the saturation by Al and bases was calculated. The simple deposition of the dolomitic corrective on the surface of the soil, twelve years after the application, allowed changes in the attributes related to soil acidity in the profile, similar to the incorporation. The use of the calcitic corrective provided more significant alterations in the attributes related to soil acidity in the profile compared to the dolomite, following its greater solubility in relation to dolomite. Almost twelve years after the natural acidity correction of the soil following the recommendations of the Soil Chemistry and Fertility Commission -RS / SC (2016), a slight reacidification of the soil of the 0-5 cm layer is observed, whose aluminum saturation is still less than 5% in the first 10 cm. Even almost twelve years after the corrective application, superficial or incorporated, still significant migration of the alkalinizing front in the soil profile to depths greater than 20 cm is perceived. A correção da acidez dos solos tem como objetivo principal neutralizar o Al3+ trocável, uma vez que a presença dessa forma de alumínio no solo causa restrição ao crescimento radicular e consequentemente a diminuição da produtividade das culturas sensíveis. Assim, em áreas cultivadas, monitorar o avanço dos atributos relacionados à acidez do solo em profundidade é fundamental para auxiliar na decisão sobre as formas de reaplicação de corretivo da acidez. O presente estudo teve como objetivo quantificar as alterações químicas do solo em profundidade, provocadas pela aplicação de corretivo, com diferentes relações Ca:Mg, de forma superficial e incorporada após 141 meses de sua aplicação. O experimento foi instalado em 2004 sob campo nativo em um Argissolo. O delineamento estatístico utilizado foi do tipo bifatorial com duas formas de aplicação (incorporado e superficial) e cinco tipos de corretivos (testemunha (0 ton/ha), e calcários com relação molar Ca:Mg de 35,5 (calcítico); 10,7; 5,9 e 2,7 (dolomítico). No mês de julho de 2016, foram abertas trincheiras em cada parcela e o solo foi amostrado até 60 cm de profundidade: a cada 1 cm até os 10 cm; a cada 2,5 cm dos 10 aos 25 cm; a cada 5 cm dos 25 aos 60 cm. As análises realizadas foram: valor de pH em água (1:1), índice TSM (Tampão Santa Maria) e teores de Ca, Mg e Al “trocáveis”. Calculou-se as saturações por Al e por bases. A simples deposição do corretivo dolomítico na superfície do solo, quase doze anos após a aplicação, propiciou alterações nos atributos relacionados a acidez do solo no perfil similares à sua incorporação. O uso do corretivo calcítico proporcionou alterações mais significativas nos atributos relacionados a acidez do solo no perfil, comparativamente ao dolomítico, seguindo sua maior solubilidade em relação a dolomita. Quase doze anos após a correção da acidez natural do solo seguindo as recomendações da Comissão de Química e Fertilidade do Solo-RS/SC (2016), percebe-se leve reacidificação do solo da camada 0-5 cm, cuja saturação por alumínio ainda é inferior a 5% nos primeiros 10 cm e migração significativa da frente alcalinizante no perfil do solo abaixo dos 20 cm.

The organic versus mineral (due to non-marine sulfate) acidity in throughfall collected at 7 RENECOFOR (RÉseau National de suivi à long terme des ÉCOsystèmes FORestiers) stations from June 1996 to May 1997 was determined. Results showed that the dominant acidity could be, in most cases, qualitatively predicted from pH. However, the dissolved organic carbon (DOC) content might also be a determining parameter, particularly in the pH range 4.5-5.5. The 7 stations can be classified according to the nature of throughfall acidity. Finally, the relative anion composition of throughfall could be estimated from pH data.